1. Technical Field
This document relates to a compression system capable of efficiently controlling a compression ratio and an air conditioning system using the same.
2. Discussion of the Related Art
Generally, air conditioners perform procedures of compressing, condensing, expanding and evaporating a refrigerant to cool or heat a confined space, such as, for example, a room.
Such air conditioners may be classified into a general single-unit type in which one indoor unit is connected to one outdoor unit, and a multi-unit type in which multiple indoor units are connected to one outdoor unit.
Also, such air conditioners may be classified into a cooling type in which a refrigerant flows only in one direction through a refrigerant cycle, only to supply cold air to a room, and a cooling and heating type in which a refrigerant flows bi-directionally in a selective manner through a refrigerant cycle, to selectively supply cold air or hot air to a room.
Hereinafter, the configuration of a conventional air conditioner will be described briefly.
FIG. 1 is a schematic diagram of an air conditioning system. The refrigerant cycle of the air conditioner includes a compressor 10, a first heat exchanger 30, an expansion valve 40, a second heat exchanger 60, and a 4-way valve 20. These elements of the refrigerant cycle are connected by a connecting line 70 functioning as a passage through which a refrigerant flows.
A refrigerant, which has been changed to a gaseous phase after heat-exchange with indoor air, is introduced into the compressor 10. The gaseous refrigerant is then compressed to a high-temperature and high-pressure state in the compressor 10. Thereafter, the gaseous refrigerant is introduced into the first heat exchanger 30, and is then changed to a liquid phase. As the refrigerant is phase-changed in the first heat exchanger 30, it discharges heat.
The liquid refrigerant from the first heat exchanger 30 is expanded while passing through the expansion valve 40, and is then introduced into the second heat exchanger 60. The liquid refrigerant is then changed to a gaseous phase in the second heat exchanger 60. As the refrigerant is phase-changed in the second heat exchanger 60, it absorbs heat from the outside of the second heat exchanger 60, thereby cooling the room. When it is desired to heat the room, this can be achieved by changing the flow direction of the refrigerant, using the 4-way valve 20, such that the refrigerant cycle operates in reverse.